Generally, a liquid material spray printer is a device for coating liquid material on a surface of a subject to print a predetermined image. As an example of such a liquid material spray printer, there is an ink-jet printer that may coats an ink material for printing.
The liquid material spray printer includes a transferring table on which a subject to be coated is mounted, a transferring device for reciprocating the transferring table so that liquid material may be coated on the subject, an ascent and descent device for ascending/descending the transferring device to a height suitable for liquid material coating, and a spray assembly installed at a substantial center of the transferring device to be capable of reciprocating in a direction perpendicular to a moving direction of the transferring table. The spray assembly contains liquid material and is provided with a nozzle capable of spraying the liquid material to the subject to be coated.
The ascent and descent device is a device that lifts a subject transferred below the spray assembly by the transferring device to a height suitable for printing liquid material. Such an ascent and descent device is disclosed in Korean Utility Model Registration Nos. 20-0300098, 20-0292979 and 20-0290203.
The ascent and descent device includes a base plate, a lead screw rotatably installed along a length of the base plate and having threads in opposite directions based on a center point, a transferring block screwed to the lead screw and selectively reciprocating within a predetermined range by rotation of the lead screw, a guide bar installed to both sides of the lead screw to guide reciprocation of the transferring block and capable of being inserted into the transferring block, and a crosslink having one end supporting a predetermined flat table and the other end to which a pair of unit links hinged to the transferring block are hinged at their center so as to lift the flat table as the transferring block is reciprocating.
However, as described above, the ascent and descent device requires many components, so much cost is needed to manufacture and assemble the components. In particular, the ascent and descent device is not suitable for lifting a flat table with a large size since only one crosslink is installed to the lead screw. That is to say, in order to apply such an ascent and descent device to a flat table with a large size, such devices should be installed at several positions so that the flat table may be stably supported and lifted. However, using several ascent and descent devices deteriorates productivity of the liquid material spray printer and causes increase of its price. Thus, there is needed an ascent and descent device that may lift a flat table with a large size more effectively.